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arXiv · 1705.07911

Noncontextual wirings

Barbara Amaral·Adán Cabello·Marcelo Terra Cunha·Leandro Aolita
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Abstract

Contextuality is a fundamental feature of quantum theory and is necessary for quantum computation and communication. Serious steps have therefore been taken towards a formal framework for contextuality as an operational resource. However, the most important component for a resource theory - a concrete, explicit form for the free operations of contextuality - was still missing. Here we provide such a component by introducing noncontextual wirings: a physically-motivated class of contextuality-free operations with a friendly parametrization. We characterize them completely for the general case of black-box measurement devices with arbitrarily many inputs and outputs. As applications, we show that the relative entropy of contextuality is a contextuality monotone and that maximally contextual boxes that serve as contextuality bits exist for a broad class of scenarios. Our results complete a unified resource-theoretic framework for contextuality and Bell nonlocality.

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Barbara Amaral, Adán Cabello, Marcelo Terra Cunha, Leandro Aolita. 2017-05-22. Noncontextual wirings. https://doi.org/10.1103/physrevlett.120.130403

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